One type of semiconductor devices are trench devices such as trench transistors, e.g. trench field effect transistors (FETs) or trench insulated-gate bipolar transistors (IGBTs). Trench devices having a high or very high integration density may include a large number (e.g. thousands, tens of thousands, hundreds of thousands, or millions, or even more) of cells, sometimes also referred to as a cell field. Already one or a few defective cells in a cell field may affect a device's operating behavior and may even render a device unusable. Thus, it may be desirable to detect devices with defective cells in a pre-test of the devices (e.g. in a front end processing stage), for example in order to prevent defective devices from being delivered to customers. In this context, it may be desirable to apply individual test potentials to one or more contact pads coupled to the cells.